JP2586478B2 - Production ratio control method and apparatus based on work ratio - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method and an apparatus for controlling a production ratio based on a work ratio, and more particularly, to a production in a factory that manufactures a plurality of types of machining-assembled works such as vehicles on the same line. The present invention relates to an improvement in a ratio control method and apparatus.

[Prior art] The process of manufacturing or assembling workpieces in a factory
In each process, a plurality of types of machining or assembling works are often manufactured on the same line. In such a case,
Depending on the degree of difficulty in assembling the processed or assembled work and the type of parts to be used, it is necessary to feed various types of processed or assembled work to each process line at an appropriate ratio.

As a method for controlling the input of a work to be input to such a production process, a method disclosed in Japanese Patent Application Laid-Open No. 61-265251 is known.

In this method, the order of loading is set in advance so that the work of each vehicle type is loaded into the production process at an appropriate ratio. Then, when it is desired to restrict the insertion of a specific vehicle type or when the ratio is changed, a setting change process is performed each time.

That is, the input of the work into the production process is controlled using the programmable controller 1 as shown in FIG.
The input order data of various works to the production process determined according to the reference setting ratio is converted into predetermined code data and stored in the memory unit 2 in advance. The coded data stored in the memory unit 2 is sequentially read out by the arithmetic control unit 3 at a predetermined timing. Then, a work input signal for the production process is output via the output unit 4.

Here, the vehicle type sequence data of various works is numerically coded for each vehicle by an appropriate arithmetic expression and stored in the memory unit 2. When the production ratio of the specific vehicle type is changed depending on the state of the post-process or the like, data indicating whether the stock amount of the post-process is large or small is input to the input unit 5, and the arithmetic control unit 3 stores the data in the memory. The data of the unit 2 is changed and output to the output unit 4.

In this manner, the input control of the work to the machining process is performed using the programmable controller.

Japanese Patent Application Laid-Open No. 55-77435 discloses that similar control is performed using a rotary switch.

[Problems to be Solved by the Invention] In such a conventional control method, since the number of works actually present in the machining process is not known, once the ratio of each work in the process is lost, There was a problem that it was difficult to return to a proper one.

The present invention has been made in order to solve such problems, and an object of the present invention is to provide a production ratio control method and apparatus capable of performing appropriate work input control according to a work ratio for each vehicle type in a machining process. And

[Means for Solving the Problems] In the production ratio control method based on the work ratio of the present invention, the work stocked in the front stock is input to the machining process via the front work stopper, and the work from the machining process is stocked in the post-process stock. Generating a loading instruction for the type of workpiece to be loaded into the machining process from the preceding work stopper according to a preset workpiece loading sequence; The process of detecting the vehicle type, the process of detecting the vehicle type of the work carried out from the post-process stock, the number of workpieces for each vehicle type in the section from the start of the processing process to the end of the post-process stock, and input to the processing process Depending on the type of workpiece to be processed and the type of workpiece to be carried out from the post-process stock, the end of the post-process stock from the start of the machining process And calculating a work ratio for each vehicle type of the work in this section while calculating the number of works in the section up to and including the work instruction. The work ratio for the work according to the input instruction is compared with the set ratio for the work. When the work ratio is smaller than the set ratio, the work is input. When the work ratio is larger than the set ratio, the work is input. Is stopped.

Further, the production ratio control device based on the work ratio according to the present invention comprises: a pre-stock in which the work is stocked; a processing step in which the work from the front stock is input via a front work stopper; and a work from the processing step. A storage unit for storing the post-process stock to be stocked, and the work input order of the vehicle type for the above-mentioned machining process, and the number of works for each type of section from the beginning of the above-mentioned machining process to the end of the above-mentioned post-process stock. By adding the number of workpieces to be input to the machining process from the front work stopper for each vehicle type and subtracting the number of workpieces carried out from the post process stock for each vehicle type, A work number counter that counts the number of works for each vehicle type in the section until the end of post-process stock, Means for calculating a work ratio for each type of work of the work, and when the work is to be put into the machining process in the work input order stored in the storage unit, And comparing means for comparing the work ratio of the work with the set ratio of the vehicle type of the work stored in advance, and controlling the input of the work from the previous stock to the processing step based on a comparison result by the comparison means. It is characterized by.

[Operation] By counting the number of workpieces input to the machining process and the number of workpieces carried out of the post-process stock for each vehicle type, the number of workpieces between the machining process and the post-process stock for each vehicle type is counted. Then, based on the result, the work ratio of each vehicle type within the above range is calculated and calculated, and the input of the work to the machining process is controlled by the work ratio. For this reason, it is possible to control the input of an appropriate work in accordance with the ratio of the work in the process.

Embodiment An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows an outline of a system according to an embodiment of the present invention.

The work carried out from the previous process (not shown) is distributed
The vehicle is classified according to vehicle type by 12 and carried into the front stock 14. In this figure, the front stock 14 is provided with three rows of rows 14A, 14B, and 14C corresponding to the vehicle type 1, the vehicle type 2, and the vehicle type 3. And the work A of the car model 1 is in the row 14A,
Work B of model 2 is in row 14B, work C of model 3 is in row 14C
To be housed. Note that these rows are usually provided in a number corresponding to the number of vehicle types.

The work in the front stock 14 is
Are sequentially input to the processing step 18.

The work that has been processed in the processing step 18
And stored in the corresponding rows 22A, 22B, and 22C of the post-process stock 22, respectively. Then, the work in the post-process stock 22 is moved to the post-process work stopper 28.
To the next step (not shown).

Also, in each row 22A, 22B, 22C of the post-process stock 22,
Pool over detection limit switches 24A, 24B, 24C and prescribed amount detection limit switches 26A, 26B, 26C are provided. Also, the type of the work to be put into the next process by the post-process work stopper 28 is detected here and output as the decrement signal b.

Then, a signal a of the detection result of the pool over detection limit switch 24 and the specified amount detection limit switch 26 and a decrement signal b for the vehicle type to be inputted into the next process by the post-process work stopper 28 are input to the production ratio control device 30. The production ratio control device 30 controls the input of the work into the processing step 18 by the previous work stopper 16 based on the input information.

Here, the production ratio control device 30 has a configuration as shown in FIG.

The signal a from the pool over detection limit switch 24 and the prescribed amount detection limit switch 26 and the decrement signal b for the type of the work to be input to the next process are input to the input section.
Entered in 32.

Then, the input unit 32 supplies the signal a to the input work calculating unit 34 and inputs the decrement signal b to the work number counter 36. The work number counter 36 counts the number of works for each vehicle type based on the decrement signal b and the increment signal c from the input work calculation unit 34.

Here, the decrement signal b is a signal relating to the type of the work to be put into the next process, and indicates the type of the work carried out from the rear stock 22. For this reason,
This shows the model of the work that has been reduced from the rear stock 22.
The increment signal c is for the vehicle type of the work for which the input instruction has been output by the input work calculating unit 34, and indicates the type of the work increased in the machining process 18.

As shown in FIG. 3, the work number counter 36 has a built-in number of vehicle type counters 38 corresponding to the vehicle type. In this example, three vehicle type counters 38 of a vehicle type 1 counter 38A corresponding to the vehicle type 1, a vehicle type 2 counter 38B corresponding to the vehicle type 2, and a vehicle type 3 counter 38C corresponding to the vehicle type 3 are incorporated. The decrement signal b is input to the minus input terminals of the respective vehicle type counters 38A, 38B, 38C. Then, the increment signal c is input to the plus input terminals of the respective vehicle type counters 38A, 38B, 38C.

When the decrement signal b is input, the count value of the corresponding vehicle type counter 38 is decremented by one, and when the increment signal C is input, the count content of the corresponding vehicle type counter 38 is incremented by one. . For this reason, it is possible to count the increase or decrease of the work for each vehicle type in the count target range.

Here, it is necessary to initially set the number of each work in the count target range in the various vehicle type counters 38. Thus, each vehicle type counter 38 outputs the number of works of each vehicle type within the counting target range.

Further, when a defective work or the like occurs in the machining process and is excluded from the production line, the count content of the work number counter deviates from the actual number. Therefore, the production ratio control device 30 has a function of changing the count of the work number counter 36. Further, the initial setting may be performed by this changing function.

A signal d, which is a signal indicating the number of works for each vehicle type, output from the work number counter 36, is input to the input work calculation unit 34. The input work calculation unit 34 includes a ratio information storage unit 42
Is also provided.

The ratio information storage unit 42 is the same as the memory unit 2 of the conventional example, and stores a work input sequence in the form of a numeric code. When a workpiece is loaded into the machining step 18 from the workpiece stopper 16, a signal e indicating the type of the workpiece or the like is supplied to the loaded workpiece calculation unit 34.

The input work calculating section 34 to which these signals are input performs the calculation in the procedure shown in FIG. 4, and outputs a signal f as a result as to whether the work can be input or not through the output section 40.
The input of the work by the front work stopper 16 is controlled by the signal f.

The procedure of this calculation will be described with reference to FIG. First, from the signal e of the coded data read from the ratio information storage unit 42, the vehicle type of the work to be inserted is determined (coded data read vehicle type determination). Next, it is determined whether or not the work of the determined vehicle type is over the pool in the post-process stock 22 (pool over). This determination is made based on the signal a from the pool over limit switch 24 corresponding to the vehicle type. If the pool is over, the loading of the work is stopped.

If the work of the model does not pool over,
It is determined whether or not there is a thinning instruction for the vehicle type (thinning code). Whether there is this thinning instruction,
Since it is included in the coded data in the ratio information storage unit 42, it is determined by this. If the code is not a thinning code, an instruction to input the work is issued.

Here, the thinning code is set in the coded data so that when the stock amount of the post-process stock 22 is equal to or more than a specified amount, the production ratio of the work of the vehicle type is reduced. Since the coded data is usually numerical data, the thinning code is set by adding a numerical value of a digit that does not affect other codes, for example, 100.

If the coded data is a thinning code, it is determined whether the stock in the post-process stock 22 of the work of the vehicle type is less than a specified amount (less than the specified amount). This specified amount indicates a standard stock amount, and if the stock amount is smaller than the specified amount, an instruction to input the work is given. It should be noted that whether the amount is smaller than the specified amount is detected by the specified amount limit switch 26, and is therefore included in the signal a.

If the stock of the work of the vehicle type is equal to or more than the specified amount, the ratio of the work actually present in the count target range (from the machining process to the stock of the subsequent process) is obtained and compared with the set ratio.

That is, since the number of works of each vehicle type is known from the signal d from the work number counter 36, the total number of works is calculated from the sum. Then, the in-process work ratio can be obtained by dividing the number of works of the vehicle type corresponding to the work to be input by this total number.

The set ratio indicates a preferable type ratio of the work, and is stored in the ratio information storage unit 42 in advance, and is read out as a signal e when necessary.

Then, when the work ratio is smaller than the set ratio, the input of the work is instructed, and when the work ratio is larger, the input is stopped.

As a result, it is determined whether or not the work of the vehicle type to be put into the machining process 18 is to be put in based on the signal e. This is output as a signal f, and the feeding of the work by the front work stopper 16 is controlled. . Further, the work number counter 36 is used for the processing step from the front work stopper 16 to the processing step.
The number of workpieces input to 18 is added for each vehicle type, and an increment signal c for the workpieces of the input vehicle type is supplied to a workpiece counter 36.

Thus, according to this embodiment, not only the information on the production ratio stored in advance, but also the post-process stock
Detailed work input control can be performed in consideration of the stock situation of each vehicle type in 22 and the ratio of the work of each vehicle type within the counting target range. Therefore, a very effective operation can be performed in the processing step.

[Effects of the Invention] As described above, according to the production ratio control method and apparatus based on the work ratio of the present invention, control is performed using the number of works for each vehicle type in the process. Work input control can be performed, and even when the ratio of the work is deviated, this can be effectively solved by the subsequent work input.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of a system according to an embodiment of the present invention, FIG. 2 is a block diagram showing a circuit of a production ratio control device in the embodiment, and FIG. 3 is a work in the embodiment. FIG. 4 is a block diagram showing a circuit of a number counter, FIG. 4 is a flowchart for explaining the operation of the input work calculating section in the embodiment, and FIG. 5 shows an example of a circuit of a production ratio control device in a conventional example. It is a block diagram. 14 ...... Front stock 16 ...... Front work stopper 18 ...... Machining process 22 ...... Back process stock 24 ...... Pool over limit switch 26 ...... Specified amount limit switch 30 ...... Production ratio control device

Claims (4)

(57) [Claims] In a production method for feeding a work stocked in a front stock into a machining process via a front work stopper, and stocking a work from the machining process in a post-process stock, a method according to a preset work input sequence. Generating a loading instruction for the type of the workpiece to be loaded into the machining process from the front work stopper; detecting the type of the workpiece loaded to the machining process; and unloading the workpiece from the post-process stock. The process of detecting the type of work of the work, the number of works for each type of work in the section from the beginning of the machining process to the end of the post-process stock, the type of work to be put into the machining process, and the work carried out from the post-process stock The number of workpieces in the section from the beginning of the machining process to the end of the post-process stock is determined for each model according to the And a calculating step of calculating a work ratio of each type of work between the vehicles, wherein when a throwing instruction is issued in the step of generating the throwing instruction, the work ratio of the workpiece according to the throwing instruction is calculated. Compare with the set ratio for the work,
A production control method based on a work ratio, wherein the work is input when the work ratio is smaller than the set ratio, and the work is stopped when the work ratio is larger than the set ratio. 2. In the post-process stock, when the number of stocked works for each vehicle type is less than a standard quantity, which is the standard number of stocks, a work is input regardless of the size of the work ratio. 2. The production ratio control method according to claim 1, wherein the production ratio is controlled by a work ratio. 3. A pre-stock in which the work is stocked, a processing step in which the work from the pre-stock is input via a front work stopper, a post-process stock in which the work from this processing step is stocked, A storage unit for storing a work input order of each vehicle type for each process, and a number of works for each type of work in a section from the beginning of the machining process to the end of the post-process stock, and from the front work stopper to the machining process By adding the number of workpieces to be input to each type of vehicle and subtracting the number of workpieces carried out from the post-process stock for each type of vehicle, the number of workpieces in the section from the beginning of the machining process to the end of the post-process stock can be reduced. A work number counter that counts the number of each type of vehicle, and a work ratio of each type of work based on the count result of the work number counter. Calculating means for calculating a work ratio in a work input sequence stored in the storage unit when the work is to be input to the machining process; And a comparison means for comparing the set ratio of the vehicle type with the set ratio of the vehicle type. The production ratio control device based on the work ratio, wherein the input of the work from the previous stock to the machining process is controlled based on a comparison result by the comparison means. . 4. A specified amount limit switch for detecting whether a stock amount of a work for each vehicle type is less than a specified amount is provided in the post-process stock, and the input of the work is controlled by this signal. 4. A production ratio control device based on a work ratio according to claim 3.